液体火箭发动机中声腔抑制不稳定燃烧的声学分析

Acoustic analysis of resonators for combustion instability suppression in liquid rocket engines

发展了声腔的分析和数值模型，对液体火箭发动机不稳定燃烧的抑制作用进行了评定。通过迭代计算研究了二维流动和温度分布变化对声腔调谐和稳定性能的影响。对不同的声腔几何尺寸和温度梯度的稳定性计算结果表明，燃烧室带有较大开口面积的声腔会更大程度地改变振荡的空间分布。这种改变而且影响了驱动和抑制燃烧的机理。讨论了在声腔设计安排中正确选择声腔的几何尺寸，且比较了不同长度和不同直径声腔的阻尼特性。通过考察声吸收系数的方法来最优化系统的阻尼，得到了可供设计参考的结论。

Analytical and numerical models are developed to assess the stabilizing impact of acoustic absorbers on liquid rocket engine combustion instability. The tuning and stability behavior of cavities in which two-dimensional flow and temperature variations exist are predicted through the application of an iterative method. Results of stabil- ity calculations performed for a variety of cavity geometries and temperature gradients indicate that adding a large open area absorber to a combustion chamber significantly alters the spatial shape of the oscillation. Selecting the right cavity geometries within the absorber arrangement is discussed. The damping characteristics of various length and various diameters resonators is compared. Optimizing the system's damping by means of the absorption coefficient would suggest. The valuable results are proposed for designer.